The day after week 3 run 1 I had a bit of discomfort in both knees. Run 2 made it worse. I took 4 days rest before attempting run 3. I finished it feeling pleased with myself but the next morning it was worse still. Long story short. 2 weeks rest, gait analasys and proper running shoes later I attempted week 3 run again. The difference is huge. I finished the run, it was hard and I put that down to the 2 week gap. My knees are almost pain free. My plan is to repeat week 3 as a build up to week 4 but if the pain returns I'll see my GP